title: Spatial regulation dominates gene function in the ganglia chain.
abstract: BACKGROUND
  To understand the molecular mechanisms of neurons, it is imperative to identify genomic dissimilarities within the heterogeneity of the neural system. This is especially true for neuronal disorders in which spatial considerations are of critical nature. For this purpose, Hirudo medicinalis provides here an ideal system in which we are able to follow gene expression along the central nervous system, to affiliate location with gene behavior.
  
  
  RESULTS
  In all, 221.1 million high-quality short reads were sequenced on the Illumina Hiseq2000 platform at the single ganglion level. Thereafter, a de novo assembly was performed using two state-of-the-art assemblers, Trinity and Trans-ABySS, to reconstruct a comprehensive de novo transcriptome. Classification of Trinity and Trans-ABySS transcripts produced a non-redundant set of 76 845 and 268 355 transcripts (>200 bp), respectively. Remarkably, using Trinity, 82% of the published medicinal leech messenger RNAs was identified. For the innexin family, all of the 21 recently reported genes were identified. Spatial regulation analysis across three ganglia throughout the entire central nervous system revealed distinct patterns of gene expression. These transcriptome data were combined with expression distribution to produce a spatio-transcripto map along the ganglia chain. This study provides a resource for gene discovery and gene regulation in future studies.
authors.affiliation: Faculty of Life Sciences, Faculty of Engineering and Institute of Nanotechnologies and Advanced Materials, Bar Ilan University, Ramat Gan, Israel 52900.
authors.forename: Dror
authors.initials: D
authors.lastname: Hibsh
authors.forename: Hadas
authors.initials: H
authors.lastname: Schori
authors.forename: Sol
authors.initials: S
authors.lastname: Efroni
authors.forename: Orit
authors.initials: O
authors.lastname: Shefi
mesh_terms: D000818:Animals; D005724:Ganglia / Q000378:metabolism*; D020869:Gene Expression Profiling / Q000379:methods*; D005786:Gene Expression Regulation; D023281:Genomics; D047709:Hirudo medicinalis; D059368:RNA Isoforms / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D017423:Sequence Analysis, RNA; D059467:Transcriptome
chemical_list: D059368:RNA Isoforms; D012333:RNA, Messenger